We have isolated desmosomes in mass quantities from bovine epidermis and further separated these into plaque and non-plaque (desmosomal "core") constituents. The latter contain all thh desmosomal glycoproteins. We have identified which desmosomal proteins are plaque-associated and which are in the intercellular adhesion zone. We have produced monoclonal antibodies to the latter proteins and plan to produce monoclonal antibodies to other desmosomal constituents. We plan to use these antibodies (1) to map the positions of the corresponding antigens in the ultrastructure of the desmosome; (2) to identify the adhesion-related desmosomal components, and (3) to study the means by which desmosomes are assembled.